Method of and apparatus for separating composite material



Sept. 6,v 1938. J. H. DICKERSON METHOD OF AND APPARATUS FOR SEPARATING COMPOSITE MATERIAL Filed Aug. 27, 1935 5 Sheets-Sheet l \J Jmas'HIeEaQ/Wa J. H. DICKERSON 2,128,918

METHOD OF AND APPARATUS FOR SEPARATING COMPOSITE MATERIAL Sept. 6 1938.

Filed Aug. 27, 1955 3 Sheets-Sheet 2 Mow M3 Sept. 6, 1938.

J. H. DICKERSON METHOD OF AND APPARATUS FOR SEPARATING COMPOSITE MATERIAL Filed Aug. 2'7, 1935 5 Sheets-Sheet 3 Patented Sept. 6, 1938 UNITED STATES PATENT OFFICE METHOD OF AND APPARATUS FOR SEPA- RATING COMPOSITE MATERIAL 27 Claims.

This invention relates to pneumatic separators for granular or lump material adapted to separate materials having different specific gravities, such as for separating coal from slate and other refuse.

More particularly the invention relates to improvements in the separating means and the process of separation described and illustrated in my copending application for patent filed September 1, 1933, Serial No. 687,770 for Coal cleaner, now Patent No. 2,022,588, and my copending application for patent filed April 24, 1935, Serial No. 18,029 for Method and apparatus for separating composite material into its components, now Patent No. 2,033,690.

Separators of this kind are constructed with reciprocating decks which carry the load of material under treatment. The reciprocation of such a deck and its load sets. up vibrations of great 20 magnitude in the machine and thus necessitates the use of a heavy and expensive supporting framework for the machine. In separators of this class, air streams are employed to aid in the separation by blowing through the mass to raise the lighter materials. When using such air streams under pressures sufficient to effect separation of the larger lumps of coal aconsiderable quantity of the smaller refuse is also carried by such air streams. However, unless a certain in- 3 0, tensity of pressure is obtained the heavier lumps of coal are not separated from the refuse.

One important object of the invention is to provide a novel form of separator having a pair of parallel reciprocating decks arranged side by 35-, side and means to reciprocate the decks in opposite directions whereby the vibrations of the machine due to the reciprocatory movements are substantially eliminated by the counterbalancing of the vibrational effects of the two decks.

A second important object of the invention is to provide a novel method and apparatus whereby the material is first subjected to air streams at a pressure sufiicient to separate and remove the larger refuse from the coal and the separated coal containing the finer refuse is then subjected to lower pressure air streams with the material kept in constant agitation.

A third important object of the invention is to provide a novel table arrangement wherein bars crossing the rifiies and above them serve to aid in supporting the larger lumps of coal so that a lower air pressure may be used to carry the bed of coal above the riflles.

A fourth important object of the invention is to 5; provide means for preventing temporary surges of, refuse from remixing refuse with the coal stream, such means being in the form of a gate arranged to adjust itself automatically to the flow of refuse so that the gate will open more widely than normal upon a temporary excess of refuse seeking passage through the gateway and will again close to normal after such excess has passed.

. With the above and other objects in, View the invention consists in a novel method of the kind described and of apparatus including novel details of construction and combinations of parts, both the method and apparatus being hereinafter fully described, and particularly pointed out in the claims, the apparatus being illustrated in the accompanying drawings wherein like characters of reference indicate like parts in the several views, and:-

Figure 1 is a plan view of one form of separator constructed in accordance with this invention;

Figure 2 is a front elevation thereof;

Figure 3 is an enlarged section on the line 3-3 of Fig. 1;

Figure 4 is a plan view of a modied form of separator;

Figure 5 is a section on the line 5-5 of Fig. 4;

Figure 6 is a detail section on the line 6-6 of Fig, 1; the view showing how the material is supported on the lower or secondary table;

Figure '7 is a plan View of the automatic refuse gate used in this invention;

Figure 8 is a section on the line 8-8 of Fig. 7.

In considering this invention, it will be described and claimed with particular reference to a coal cleaner for separating coal from slate and otherrefuse of greater specific gravity. It is, however, to be understood that neither the method nor the apparatus is restricted to this particular use but both method and apparatus for separating a mixture having components of different specific gravities whereof coal is typical of a lighter material and slate of a heavier material. It is accordingly to be understood that wherever coal is used in this specification and the claims, it is to be interpreted in its broad sense as indicating the light component of a mixture and refuse and slate are to be taken as referring to the heavier component of such a mixture.

It is to be further noted that the form shown in Figures 1 to 3 shows two inclined sections A and B arranged side by side with the section B slightly below the plane of the section A and both being inclined in the same direction. The

form shown in Figures 4 and 5 has two sections C and D synclinally arranged. The sections A, C and D are substantially identical in construction so that like reference characters will be used on these sections.

In order to supply material to the apparatus, there is provided at the upper edge of the section A in the first form, and at the upper edge of the section C in the second form, a bin I. At the lower end of the bin I, there is provided a transversely inclined plate 2 which is carried by the reciprocating frame member 2a. An adjustable gate 3 is mounted on the bin I to cooperate with the feeder plate 2 and regulate the discharge from the bin in accordance with the height of the opening between the plate 2 and gate 3. For the section D of the second form, there is provided a chute Ia having an inclined plate 2d at its lower end, this inclined plate overhanging but free from the reciprocating frame member 2a of this section. A revolving feeder wheel 26 is mounted in the chute Ia to feed material downwardly onto the plate 2d. These are optional forms of feed. In each instance, the plates deliver the mixed materials to an inclined deck 5 at its upper edge portion and overhangs this upper edge portion. The deck 5 is supported by a frame, the upper side of which is formed by the member 2a, while the lower side is shown at 5a. In the cove or recess formed by the overhang of the inclined plate there is provided an upstanding air duct 2b terminating in an upwardly inclined delivery nozzle 20, which extends along beneath the edge of the plate 2. By the provision of this blower nozzle much of the lighter material, such as coal, is blown out of the stream descending from the plate, while the heavier material, such as slate, drops onto the upper edge portion of the deck and finds its way into the channel 4 formed by the deck and the air duct and nozzle. Riflies 6 extend forwardly from the lower to the upper portion of the deck 5, these rifiies terminating upwardly and forwardly of the deck to leave a clear space therealong forming a species of channel for the heavier material.

The member 2a is continued forwardly of the bin I'as at I. The forward end of the deck terminates in an inclined edge extending forwardly at an angle across the front of the deck and carrying a guard member Ia which is thus at an obtuse angle with the member 1. These members I and la form a banking bar. Supported by the deck 5, the member I and the rear part of the member la, is a transversely curved spreader plate 8 arranged with its concave side facing the riiiles 6. This plate is pervious to streams of fluid, such as air, being provided with holes 8a for that purpose. This spreader plate 8 has its lower part flush with the deck and has its receiving end very narrow and inclined upwardly from the deck. The plate increases in height and width to the end of the member I and then it curves horizontally to its discharge end. Forward of the spreader plate 8 is a concentrator plate 9. This plate is transversely curved to provide a vertical leg which extends along the member 1a and an incline-d leg which overhangs the forward end portion of the deck 5. The plate 9 is inclined downwardly from the end adjacent the plate 8 to its delivery end.

In the first form of the invention, the second or lower section B is supported on frame members 5e and carries at its upper edge a plate 5/ extending upwardly to prevent material from dropping off the deck at this place. A delivery plate 59 is carried by the deck 5 and extends over this plate 5 so that material may flow from the deck section A to the deck section B and leave a passageway 4a for the free forward movement of the finer refuse. The deck 5d is provided with riffies 6a similarly arranged to the riffles 6. Resting on top of these rifiles 6a is a series of coal supporting bars 6b arranged substantially at right angles to the rifiies 6a. In each of the sections A and B of the first form and C and D of the second form, the spaces between the lower or delivery ends of the rifiles are partially closed by a spillway member II which extends along the lower edge of the deck and is provided in its upper edge with spaced notches Ila which lie adjacent the lower faces of said rifiies. The forward end of the member la is spaced from the forward end of the member 5a to provide a delivery channel for the escape of the heavier material or refuse from the deck. An adjustable gate I2 is pivoted at the forward end of the member 5a and the purpose of this gate is to divide the heavier material, fully separated from the mixture of heavy and light materials, from the middlings or that part of the material which still retains some of the lighter constituent mixed with or attached to the heavier material. A delivery spout I l extends from the opening between the members I2 and la.

In order to hold the gate I2 yieldably in adjusted position there is provided on the member 1a a yoke bracket I2a wherethrough slides a screw I 2b which is screwed through a nut I2c mounted between the arms of the bracket I2a. This screw extends slidably through an opening in the gate I2 and is provided with a nut I2d limiting closing movement of the gate I2, the nut IZd resting against what may be termed the inner face of said gate. On the free end of the screw is a nut or collar I2e between which and the outer face of the gate I2 there is a spring I2 surrounding the screw and urging the gate against the nut I 2d. By this means the gate cannot close beyond the position to which it is adjusted but may open under pressure such as would be induced by an excessive amount of material flowing between the gate and the member 1a.

A divider I3 is movably mounted adjacent the gate I2 at the lower edge of the deck to divide the middlings from the lighter material, the former flowing into a middlings hopper I5, while the latter flows into a hopper I6 which may be termed the clean material hopper.

As a means of oscillating each deck, there is provided a connecting rod I! attached to an end frame member Ila of the deck. Each rod is actuated by an eccentric I'lb fixed on a shaft I'Ic driven by a motor I8. In each form the eccentrics are oppositely arranged to move one deck forwardly as the other is moved rearwardly. To permit the deck to oscillate links III are provided, these links being pivotally connected at their upper ends to the deck, and at their lower ends to fixed sills or beams 20, forming the support for the device. Beneath the riflies 6 and the deck 5 are partitions So, which are aligned with the re spective rifiles to form a grating at the upper ends of the air chests 2|, which receive air from the supply pipe 22. Flexible connections 23 connect the chests 2I to branches 22a of the pipe 22, so as to permit free movement of the deck. Each of the branches 22a is provided with a fixed partition 2 la and a flexible connection 23a to a fixed partition 24 within the air chest which termi- Cit nates against the members 60 so as to cause desired distribution of the air. Moreover, gates are provided in each branch 22a, and these gates are adjustable so that the air from the pipe 22 may be fed to the deck on one side, and the other of the partition 24 in such manner as to provide a desired adjustable distribution of the air volume.

The deck is made pervious to the air from the pipe 22 by means of a multiplicity of vents 50.

In the form shown in Figs. 4, 5 and 7 a short guide 28 is mounted on the deck 5 at the lower end of the plate 9 and is inclined so that its forward end is closer to the banking bar "la than its rear end. In connection with the concentrator plate 9, this guide 28 somewhat retards the movement of the heavier material or refuse so as to maintain a substantially uniform width of the stream leaving the concentrator along the banking bar independently of temporary changes in the quantity of heavier material or refuse in the mixture of raw coal.

In the form of the invention shown in Figures 1 to 3 a secondary banking bar 29 is provided which has at its upper end a gate 30 adjustably mounted in the same manner as the gate l2 and this gate also takes the place of the member 23 just described. In the upper deck 5 of this form there is provided an opening 3! leading to a middlings chute 32.

In the operation of these devices the motor is started and imparts to the two decks and the parts carried thereby reciprocatory movements in which one deck reciprocates in one direction While the other reciprocates in the opposite direction, thereby substantially counterbalancing the vibratory stresses set up in the frame by the to and fro movements of the decks. In each form the gate 3 is adjusted so that a thin stream of mixed material will flow past the nozzle 20 and, in the form shown in section D, the feeding paddle is similarly adjusted in speed. Also, in the form of Figures 1 to 3 the gates 25 are adjusted so that there will be relatively high velocity in the air streams flowing through the orifices 50 of the upper deck and a relatively low velocity in the air streams flowing through the orifices 5c of the lower deck. Similarly, in the form shown in Figures 4 and 5, the gates 25 may be adjusted for velocities of air suited to the different grades of material fed over the two decks. The air issuing through the nozzle 20 blows through the descending sheet of raw coal and the coal and refuse are partially separated at this place, much of the coal being blown out onto the riffle provided portion of the deck, while the refuse drops into the channel 4 or is guided into it by the riffies 6 along which it is forced by the reciproeating action of the deck along the line of the arrow shown in Fig. 1. While the coal is lifted over the riffies by the upward current of air and carried away from the heavier gravity material some of it will be trapped and carried along with the refuse stream. although this will be greatly reduced by the special feed arrangement which gives a free passageway for the refuse stream after it crosses the thin raw feed stream. With each reciprocating stroke the refuse in the channel 4 is advanced by its inertia forwardly on the deck 5 and gradually passes into the concave side of the spreader 8 where it is spread out so coal which may have been trapped with the refuse is brought to the top by the action of the deck and the upward current of air blown through the openings 8a. The coal being relatively light will not have the i'nertia'of the refuse. This difference together with the lifting current of air and gravity'will assist the movement of the coal back to the riffled part of the deck 5. Meanwhile the partly cleaned coal is spread out over the rifiles 6 in a comparatively thin bed. The heavier gravity material drops out of this bed, which has a fluid like consistency due to the upward current of air through the vents 5c, and goes. to the bottom of the deck between the riffles. This material being too heavy to be held up by the air is trapped by the rifiies 6 and guided forwardly by them due to the inertia of the material and the reciprocating motion of the deck until it passes from the-upper end of the riffles 6 to join the flowing stream of refuse along the top'of the deck 5 and the banking bar Ia, while the lighter coal flows down and over the rifiles 6. In the form shown in Figures 1 to 3, the coal from the section A then passes onto the section B where it is similarly treated. It will be noted that the middlings pass into the opening 3| while the refuse passes down through the channel formed by the lower banking bar 1a and the auxiliary banking bar 29.

With the upper section a stronger air current and more violent agitation is used than for the lower section. This will remove the coarser refuse but much of the finer refuse will be blown over and pass off with the treated coal. The shorter riffles obtained by splitting the deck is an important feature, because refuse niust pass to the upper end of the riflies to be discharged, and when they are long or there is much refuse the refuse will interfere with the air, causing an uneven distribution of air and an uneven bed of coal on the deck, thus reducing the efficiency of the separator. The preliminary air action on the feed stream and the stronger air current for the upper section will make it possible to treat wet coal more satisfactorily than heretofore with this With the strong air current I type of separator. passing through the feed stream, and a strong current upward through the upper deck section, much of the moisture will be freed before the treated coal reaches the lower deck section, so when it is retreated with weaker air currents there will be little tendency for it to clog up the deck, which is caused by wet, sticky coal and light pressure.

The projecting discharge plate So on the upper section keeps the treated coal from dropping along the upper edge of the lower section and a refuse channel 4a, is left for the free forward movement of refuse the same as along the upper deck feeder. The auxiliary banking bar is used on the lower section to keep the refuse from the lower section away from that coming from the upper section, until the latter is concentrated and then the two streams are united.

On the lower section the coal supporting bars 6b are placed over the tops of the deck riflles at approximately the angle the coal would flow without their use. They are inclined slightly forward and spaced parallel about the width apart of the largest coal being treated so they do not act as screen bars, for the coal will be free to touch the bottom without the air action. As the air lifts the coal above the rifiles the larger pieces will come in contact with the supporting bars. The lateral inclination of these bars and arching of the coal between them will help the air to lift the coal and keep it above the deck rifiles. Both along the tops of the bars and along their upper laterally inclined sides part of the weight of the coal will be transferred to the bars and less air will be required to hold up the coal. For this reason, a lower air pressure may be used. The supporting bars will also tend to make the coal move faster and keep the larger coal near the top, while the air alone would naturally bring the finer coal in the top. This is a decided advantageas the coarser refuse has been removed on the upper section, and with the coarser coal at the top of the bed the air will have a better cleaning action on the smaller sizes. For the same reason the rifiies on the lower section will not need to be as high and only enough air will have to be supplied to keep the coal moving along above the riffies with the aid of supporting bars. This will greatly increase the efilciency of the deck, and permit the cleaning of a greater size range without rescreening and retreatment on a separate cleaner, which increases the amount of equipment, cost of cleaning and degradation of the coal.

At the discharge end of the lower section a movable divider I3 is used to separate middlings from clean coal if desired. Middlings is a term used to designate a mixture of the lighter refuse, coal attached to pieces of bone or refuse, to coal which has been trapped with the refuse stream, and to an overflow of refuse when there is a temporary overflow from very dirty coal.

By my method of recleaning refuse there should be no coal left in the refuse stream, and temporary changes in the amount of refuse will be taken care of so as not to overflow into the middlings stream. The automatic refuse or slate gate 42 with automatic adjustment for surges in the slate stream will also help this condition. With these improved features, and a coal which does not tend to stick to the impurities there Will be many cases where the middlings may be mixed with the coal or thrown away with the refuse, depending on the allowable amount of ash. Where bone and slate stick to the coal the middlings should be crushed to free the coal and then retreated. Chutes 34 and an elevator 35 may be used if desired to put the middlings back on the separator for retreatment with or without crushing.

Where a separator is divided, as in Figures 4 and 5, into two sections discharging its products into hoppers at the center between them, the two sections may be used to clean different sizes or kinds of coal, and the deck sections, air supply and rocking motion adjusted for the difference in the material treated.

The refuse gate l2 may be arranged or adjusted to make the desired out between the refuse and middlings, or between refuse and the clean coal product. The receiving end of this gate is turned outward at 33 so that an increase in the refuse stream will exert a pressure to open the gate wider. This is permitted by the use of the spring and an adjustment means which will permit it to open further from the point of adjustment, and the spring will reduce the opening when the pressure is released.

In both forms the coal finally passes out over the notched spillway into the hoppers, being divided into middlings and cleaned coal by the dividers l3.

As the refuse stream flows along the banking bar hr. after passing from the spreader 8, it moves along the concentrator plate 9 where it is concentrated into a relatively compact stream which tends to rise up on the banking bar la but is limited in doing so by the overhang of the plate 9. The plate acts to rollthe upper part of the stream away from the banking bar '!a as the stream moves along, so that the material of the stream as it passes along the concentrator 9 tends to turn in a spiral path, and any coal left in the refuse stream will be brought to the surface where it can work out of the refuse stream. The action of the deck 5 will cause the heavier refuse to mass against the banking bar Ta or concentrator plate 9, and this action together with the upward current of air through the deck and gravity will all assist coal in its movement out of the refuse stream.

Obviously, this banking action of the refuse on the lower deck in the form shown in Figures 1 to 3 will be effected along the auxiliary banking bar 29 until the stream reaches the lower end of that bar when it will unite with the refuse stream from the upper deck.

The middlings pass from rifiie to riffle in a line parallel and close to the refuse stream. The outer edge of the refuse stream away from the banking bar 1a is the lighter part of the refuse and is usually mixed with the middlings. It is usual to have some form of cutting finger or gate such as if or 39 to separate middlings from the clean coal if it is desired to collect these three products separately. If the amount of refuse changes, the gate 52 must be adjusted or some of the refuse or middlings will go to the wrong discharge point. By lowering the concentrator 9 at its discharge end and the use of the bar 28 the refuse stream is held back a little when there is a temporary increase in the amount of refuse, and let out as it decreases so there is a more uniform discharge and less occasion to adjust the gate to keep refuse from going out with the middlings or coal to be lost with the refuse. The refuse passes out the spout 14, while the middlings go to the hopper i5, and clean coal to the hopper i6. Middlings may be thrown away with the refuse, remixed with the coal, or retreated before or after crushing.

It is desired to point out that the coal supporting bars are preferably made of copper or other metal and may be spot-welded to the tops of the riflles. While this is the preferred means of attachment, these bars may be attached to the rifiies in a different manner.

The supporting bars are preferably about oneeighth of an inch thick and from one-half A to one and one-half (1 inches in height, de-

pending upon the character and size of the material being treated and on how much air space is desired between the tops of the riifles and the bed of coal carried above them by the air cushion. The above dimensions are merely illustrative and are not to be interpreted as a limitation as the size of the supporting bars will vary in accordance with the character of the material treated and the other conditions of treatment.

There has thus been provided a simple and efficient device of the kind described and for the purpose specified.

There has also been provided an eiiicient and economical method for separating entrained lighter material from a mass containing a relatively small quantity of light material mixed with a relatively large quantity of heavy material, and it is to be noted that this method may be carried into execution by any suitable means.

What is claimed is:-

1. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for effecting a preliminary separation of heavier refuse from raw coal, a secondary inclined separating deck receiving a stream of partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, riflies on said decks arranged at an angle to the direction of reciprocation, a passageway for refuse at the upper side of said secondary deck, means for maintaining the moving refuse in said passageway free of contact with the feed stream passing from said primary deck, over said passageway, and onto the secondary deck, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means on each deck for independently collecting middlings and refuse and means to reciprocate said decks.

2. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for effecting a preliminary separation of heavier refuse from raw coal, a secondary inclined separating deck receiving a stream of partially cleaned coal from the primary deckand separating the remainder of the refuse therefrom, said secondary deck being provided with a passageway for refuse adjacent its upper side, means for maintaining the moving refuse in said passageway free of contact with the feed stream passing from said primary deck, over said passageway, and onto the secondary deck, riflies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively lowpressure air to the secondary deck, and means to reciprocate said decks.

3. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for effecting a preliminary separation of heavier refuse from raw coal, a secondary inclined separating deck receiving a stream of partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, said secondary deck being provided with a passageway for refuse adjacent its upper side, means for maintaining the moving refuse in said passageway free of contact with the feed stream of partially cleaned coal passing from said primary deck over said passageway and onto the secondary deck, riiiles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means to reciprocate said decks, means to deliver refuse collected from the primary deck to the forward part of the secondary deck, and means to Withdraw coal middlings from the primary deck independently of the secondary deck.

l. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for separating heavier refuse from raw coal, a secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, rifiies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means to reciprocate said decks, and coal supporting bars above and crossing the riiiles of the secondary deck in the direction of coal flow on said deck.

5. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for separating heavier refuse from raw coal, at secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, riffles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means to reciprocate said decks, coal supporting bars above and crossing the rifiies of the secondary deck in the direction of coal flow on said deck, and means to deliver the partially cleaned coal and the separated refuse from the primary deck to separate areas of the secondary deck.

6. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for separating heavier refuse from raw coal, a secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, riilies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means-to supply air to said apertures, means to control the flow'of'air through the apertures to provide relatively high pressure air to the primary deck and relatively low pres sure air to the secondary deck, means to reciprocate said decks, coal supporting bars above and crossing the rifiles of the secondary deck in the direction of coal flow on said deck, means to deliver the partially cleaned coal and the separated refuse from the primary deck to separate areas of the secondary deck, and other means to Withdraw coal middlings from the primary deck independently of the secondary deck.

7. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for separating heavier refuse from raw coal, a secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, rifiles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means to reciprocate said decks, substantially aligned banking bars extending diagonally to the direction of reciprocation and across the forward ends of said decks, and an auxiliary banking bar extending along the lower part of the primary deck banking bar and the upper part of the secondary deck banking bar in spaced relation thereto to form a channel for deliveringrefuse from the primary to the secondary deck, the lower end of the auxiliary banking bar forming a concentrating means for the refuse of the secondary deck.

8. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for separating heavier refuse from raw coal,

a secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, riflies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means to reciprocate said decks, coal supporting bars above and crossing the rifiies of the secondary deck in the direction of coal flow on said deck, substantially aligned banking barsextending diagonally to the direction of reciprocation and across the forward ends of said decks, and an auxiliary banking bar extending along the lower part of the primary deck banking bar and the upper part of the secondary deck banking bar in spaced relation thereto to form a channel for delivering refuse from the primary to the secondary deck, the lower end of the auxiliary banking bar forming a concentrating means for the refuse of the secondary deck.

9. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for separating heavier refuse from raw coal, a secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, riflles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means to reciprocate said decks, substantially aligned banking bars extending diagonally to the direction of reciprocation and across the for- Ward ends of said decks, and an auxiliary banking bar extending along the lower part of the primary deck banking bar and the upper part of the secondary deck banking bar in spaced relation thereto to form a channel for delivering refuse from the primary to the secondary deck, the lower end of the auxiliary banking bar forming a concentrating means for the refuse of the secondary deck, a middlings discharge chute leading from a point in the primary deck between the side of the auxiliary banking bar and the riffles, a gate pivoted at the upper end of the auxiliary banking bar to divide the refuse from the middlings, and means to hold said gate in adjusted position.

10. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for separating heavier refuse from raw coal, a secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, riflies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet aperture, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means to reciprocate said decks substantially aligned banking bars extending diagonally to the direction of reciprocation and across the forward ends of said decks, an auxiliary banking bar extending along the lower part of the primary deck banking bar and the upper part of the secondary deck banking bar in spaced relation thereto to form a channel for delivering refuse from the primary to the secondary deck, coal supporting bars above on and crossing the riffles of the secondary deck in the direction of coal flow on said deck, a middlings discharge chute leading from a point in the primary deck between the side of the auxiliary banking bar and the rifiies, a gate pivoted at the upper end of the auxiliary banking bar to divide the refuse from the middlings, and means to hold said gate in adjusted position.

11. In a separator for separating refuse from coal, an inclined reciprocable deck for separating heavier refuse from raw coal, rifiles on said deck arranged at an angle to the direction of reciprocation, said deck being provided with a multiplicity of air jet apertures, means to supply air to the said apertures, means to control the flow of air through the apertures to provide relatively high pressure air on the upper part of said deck, and relatively low pressure air to the lower part of said deck, and coal supporting bars above and crossing the riffles of the low pressure area in the direction of coal flow on said deck.

12. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for separating heavier refuse from raw coal, a secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, riflles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure air to the primary deck and relatively low pressure air to the secondary deck, means to reciprocate said decks, substantially aligned banking bars extending diagonally to the direction of reciprocation and across the forward ends of said decks, an auxiliary banking bar extending along the lower part of the primary deck banking bar and the upper part of the secondary deck banking bar in spaced relation thereto to form a channel for delivering refuse from the primary to the secondary deck, the lower end of the auxiliary banking bar forming a concentrating means for the refuse of the secondary deck, a middlings discharge chute leading from a point in the primary deck between the side of the auxiliary banking bar and the rifiles, a gate pivoted at the upper end of the auxiliary banking bar to divide the refuse from the middlings, means to hold said gate in adjusted position, a refuse discharge chute at the lower end of the first banking bar on the secondary deck, a middlings discharge chute on said secondary deck adjacent the refuse discharge chute, a pivoted gate between the refuse discharge chute and middlings discharge chute of the secondary deck, and means to hold the last mentioned gate in adjusted position.

13. The method of separating material having heavy and light components, comprising subjecting said material in a transversely inclined bed having an upper section and a lower section, and a heavy component lane therebetween, to a series of reciprocating impulses transverse to the direction of the bed, subjecting the layer of material to the heavy refuse stream, and some of the smaller size heavy components together with the light components flow towards the lower part of the upper section, discharging said mixture to the upper side of the lower section over and beyond the heavy refuse stream, and concentrating said mixture on the lower section of the inclined layer in the presence of relatively low pressure air streams to separate the mixture into light gravity components and heavy gravity components, and collecting said heavy gravity components in the heavy component lane.

14. The method of separating material having heavy and light components, comprising subjecting said material in a transversely inclined bed having an upper section and a lower section, and a heavy component lane therebetween, to a series of reciprocating impulses transverse to the direction of the bed, subjecting the layer of material on the upper section of the inclined bed to a multiplicity of relatively high pressure air streams, directing the material on the upper section of the inclined layer transversely of the direction of reciprocation of the machine, whereby the heavier larger size gravity components flow toward the upper part of the upper section to the heavy refuse stream, and some of the smaller size heavy components together with the light components flow towards the lower part of the upper section, discharging said mixture to the upper side of the lower section over and beyond the heavy refuse stream, and concentrating said mixture on the lower section of the inclined layer in the presence of relatively low pressure air streams to separate the mixture into light gravity components and heavy gravity components, and collecting said heavy gravity components in the heavy component lane, and uniting the heavy refuse components from the respective sections into a single stream.

15. The method of separating mixed components varying in size and of different specific gravities comprising subjecting said material in a transversely inclined bed having an upper section and a lower section and a heavy component refuse channel therebetween, to a series of reciprocating impulses transverse to the direction of the bed, subjecting the layer of material on the upper section of the inclined bed to a multiplicity of relatively high pressure air streams passing upwardly through the bed from below, the larger size heavy gravity components dropping out of the bed and moving at an angle to the flow of the remaining material in the inclined bed, discharging said remaining material from the lower side of said upper section over and beyond said heavy component refuse channel of the lower section, subjecting said material to a multiplicity of low pressure air streams, concentrating the larger lighter gravity components of the mixture adjacent the surface of the air-treated material bed, while permitting the smaller size heavy refuse to drop out of the inclined bed, directing said refuse to said refuse channel and the lighter gravity material downwardly to be discharged along the lower side of the lower section, directing the refuse from'the upper section to the lower section, uniting the refuse from the two sections, and discharging the so-united refuse mixture at the forward end of the separator.

16. In a pneumatic separator for separating coal from refuse, a primary inclined reciprocable separating deck for effecting a preliminary separation of the heavy gravity refuse from the raw coal, a secondary inclined reciprocating deck adapted to receive the feed stream from the primary deck and to separate the remaining refuse from the coal, rifiies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, a passageway for refuse at the upper side of said secondary deck, a discharge chute extending from the lower side of the primary deck and over said passageway, whereby refuse in said passageway is maintained free of contact with the feed stream of partially cleaned coal passing from said discharge chute to the secondary deck, means above and crossing the riffles on the secondary deck in the direction of the coal flow on said deck to assist the air in supporting the bed of coal above the riffles while allowing the refuse to drop down between the riffles, and means to reciprocate said decks.

17. In a pneumatic separator for separating coal from refuse, a primary inclined reciprocable separating deck for effecting a preliminary separation of the heavy gravity refuse from the raw coal, a secondary inclined reciprocating deck adapted to receive the feed stream from the primary deck and to separate the remaining refuse from the coal, rifiies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to adjust the amount of air supplied to different sections of at least one of said decks, a passageway for refuse at the upper side of said secondary deck, a discharge chute extending from the lower side of the primary deck and over said passageway, whereby refuse in said passageway is maintained free of contact with the feed stream of partially cleaned coal passing from said discharge chute to the secondary deck, means above and crossing the riiiles on the secondary deck in the direction of the coal flow on said deck to assist the air in supporting the bed of coal above the riffles while allowing the refuse to drop down between the rifiles, and means to reciprocate said decks.

18. In a pneumatic separator for separating coal from refuse, a primary inclined reciprocable separating deck for effecting a preliminary separation of the heavy gravity refuse from the raw coal, a secondary inclined reciprocating deck adapted to receive the feed stream from the pri mary deck and to separate the remaining refuse from the coal, riffles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, a passageway for refuse at the upper side of said secondary deck, a discharge chute extending from the lower side of the primary deck and over said passageway, whereby refuse in said passageway is maintained free of contact with the feed stream of partially cleaned coal passing from said discharge chute to the secondary deck, coal supporting bars above and crossing the rifiles of the secondary deck in the direction of coal flow on said deck, and means to reciprocate said decks.

19. In a separator for separating coal from refuse, a primary inclined reciprocating deck for eifecting a preliminary separation of heavy gravity refuse from raw coal, a secondary inclined reciprocating deck adapted to receive the feed stream from the primary deck and to separate the remaining refuse from the coal, rifiles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, a passageway for refuse at the upper side of said secondary deck, means for maintaining said refuse free of contact with the feed stream passing from said primary deck, over said passageway, and onto the secondary deck, means to reciprocate said decks, banking means extending diagonally to the direction of reciprocation and across the forward ends of said decks, and an auxiliary banking means extending along the lower part of the primary deck banking means and the upper part of the secondary deck banking means in spaced relation thereto to form a channel for delivering refuse from the primary to the secondary deck, the lower end of the auxiliary bank! ing means forming a concentrating means for the refuse of the secondary deck.

20. In a separator for separating coal from refuse, a primary inclined reciprocating deck for effecting a preliminary separation of heavy gravity refuse from raw coal, a secondary inclined reciprocating deck adapted to receive the feed stream from the primary deck and to separate the remaining refuse from the coal, riifles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, a passageway for refuse at the upper side of said secondary deck, means for maintaining said refuse free of contact with the feed stream passing from said primary deck, over said passageway, and onto the secondary deck, means to reciprocate said decks, banking means extending diagonally to the direction of reciprocation and across the forward ends of said decks, an auxiliary banking means extending along the lower part of the primary deck banking means and the upper part of the secondary deck banking means in spaced relation thereto to form a channel for delivering refuse from the primary to the secondary deck, the lower end of the auxiliary banking means forming a concentrating means for the refuse of the secondary deck, means to discharge middlings from the primary deck, and means at the upper end of the auxiliary banking means to divide the refuse from the middlings.

21. In a separator for separating lighter gravity material from heavier gravity material, a separating deck, means for reciprocating the deck, rifiles on said deck arranged at an angle to the direction of reciprocation of the deck, said deck being provided with a multiplicity of air jet apertures, means to supply air to said apertures, and coal supporting bars supported in a position laterally thereof at an angle to the vertical above said riiiles and crossing the latter in the direction of the coal flow on said deck to assist the air in supporting the lighter gravity material above the riflles, said bars being constructed and arranged to allow said heavy gravity material to drop down between the riflies.

22. In a separator for separating coal from refuse, a separating deck, means for reciprocation of the deck, riflles on said deck arranged at an angle to the direction of reciprocation, said deck being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide relatively high pressure and low pressure areas, and coal supporting bars in clined upwardly from the rlflies and. forwardly of the deck above and crossing the rifiies in the direction of the coal flow on said deck to assist the air in supporting the bed of coal above the riffles said bars being constructed and arranged to allow the said bed of material to drop down between the riffies when air pressure is Withdrawn.

23. In a pneumatic separator for separating coal from refuse, a primary reciprocating separating deck having a banking bar and sloping to one side for effecting a partial separation of heavy gravity refuse from raw coal, a secondary reciprocating deck having a banking bar and sloping in the same direction as the primary deck, said secondary deck being adapted to receive the partially cleaned coal from the primary deck, and to separate the remaining refuse from the coal, riflies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, a passageway for refuse at the upper side of said secondary deck, means for maintaining the moving refuse in said passageway free of contact with the feed stream of partially cleaned coal passing from said primary deck, over said passageway, and onto the secondary deck, and means to reciprocate said decks.

24. In a separator for separating heavy gravity material from light gravity material, an upper reciprocable separating deck having a banking bar and sloping to one side for effecting a partial separation of the heavy gravity material from the light gravity material, a lower reciprocable separating deck having a banking bar and sloping in the same direction as the upper deck, said lower deck being adapted to receive the partially separated material from the upper deck, and to separate the remainder of the heavy gravity material from the light gravity material, riflles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to reciprocate the decks, a passageway for the heavy gravity material at the upper side of the lower deck, a discharge chute extending from the lower side of the upper deck and over said passageway, whereby the heavy gravity material in said passageway is maintained free of contact with the feed stream of partially separated material from said discharge chute of the upper deck, above said passageway, and onto the lower deck, the heavy gravity material passing along the banking bars of both decks to discharge at the extreme end of the lower separator, while the lighter gravity material is discharged along the lower side of the lower separator.

25. In a pneumatic separator for separating coal from refuse, a primary reciprocating separating deck having a banking bar and sloping to one side for efiecting a partial separation of heavy gravity refuse from raw coal, a secondary reciprocating separating deck having a banking bar and sloping in the same direction as the primary deck,

said secondary deck being adapted to receive the partially cleaned coal from the primary deck, and to separate the remaining refuse from the coal, rifiies on said decks arranged at an angle to the direction of reciprocation, each of said decks be ing provided with a multiplicity of air jet apertures, means to supply air to said apertures, a passageway for refuse at the upper side of said secondary deck, a discharge chute extending from the lower side of the primary deck and over said passageway, whereby refuse in said passageway is maintained free of contact with the feed stream of partially cleaned coal passing from said discharge chute to the secondary deck, and means to reciprocate said decks.

26. In a separator for separating coal from refuse, a primary inclined reciprocable separating deck for effecting a preliminary separation of heavier refuse from raw coal, a secondary inclined separating deck receiving a stream of partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, said secondary deck being provided with a passageway for refuse adjacent its upper side, means for maintaining the moving refuse in said passageway free of contact with the feed stream passing from said primary deck, over said passageway, and onto the secondary deck, rifiles on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide a relatively large quantity of air to the primary deck and a relatively small quantity of air to the secondary deck, and means to reciprocate said decks.

27. In a separator for separating coal from refuse, a primary inclined reciprocable Separating deck for separating heavier refuse from raw coal, a secondary inclined separating deck receiving the partially cleaned coal from the primary deck and separating the remainder of the refuse therefrom, riflies on said decks arranged at an angle to the direction of reciprocation, each of said decks being provided with a multiplicity of air jet apertures, means to supply air to said apertures, means to control the flow of air through the apertures to provide a relatively large quantity of air to the primary deck and a relatively small quantity of air to the secondary deck, means to reciprocate said decks, substantially aligned banking bars extending diagonally to the direction of reciprocation and across the forward ends of said decks, and an auxiliary banking bar extending along the lower part of the primary deck banking bar and the upper part of the secondary deck banking bar in spaced relation thereto to form a channel for delivering refuse from the primary to the secondary deck, the lower end of the auxiliary banking bar forming a concentrating means for the refuse of the secondary deck.

JAMES H. DICKERSON. 

